KR20020056022A - Potocuring banish composition and its usage - Google Patents

Abstract

PURPOSE: Provided are a paint composition showing excellent flexibility, hardness, ultraviolet curing, abrasion resistance, weatherability, and chemical resistance when used in application requiring for flexibility such as plastic bottle, telephone, sheet, film, and so on, and a molded plastic article coated with the composition. CONSTITUTION: The photocurable paint composition comprises 10-70 parts by weight of urethane acrylate of formula 1, 10-30 parts by weight of specifically modified polyfunctional monomer, 10-50 parts by weight of reactive monomer, 0.1-20 parts by weight of photosensitizer, 10 parts by weight or less of leveling agent, and small amount of additives. In the formula 1, R1 represents hydrogen atom or methyl group, R2 represents (CH2)n or formula a and b(wherein n is an integer of 2-6, R4, R5 and R6, which are same or different, represent a linear alkyl group, provided that at least one of R4, R5 and R6 is methyl group, R7 represents an aliphatic, cycloaliphatic or aromatic compound), X represents formula c(wherein b is an integer of 5-20, c is an integer of 2-5, Y is hydrogen atom or methyl group).

Description

Photocurable coating composition and plastic molded article coated thereon {Potocuring banish composition and its usage}

The present invention relates to a photocurable coating composition and a plastic molded article coated with the same, and more particularly to a coating composition including a photocurable urethane acrylate resin, a monomer, a photoinitiator, and the like, in order to provide excellent flexibility and curability. Nitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polystyrene (PS), polyvinyl chloride (PVC) plastic bottles, It relates to molded articles such as telephones, sheets, films and the like.

In general, many plastic products that benefit our surroundings are indispensable as a resource to make life easier.

Plastics have unique properties depending on the type.The advantages of plastics, such as glass and metal, are lighter, cheaper, and easier to process, making them more suitable for home appliances, automotive parts, electronic parts, construction materials, aircraft parts, and cosmetic cases. It is applied in various fields that can be easily encountered in daily life. However, these plastic products are coated to protect their surface or improve their appearance.

At this time, various paints can be applied, especially UV-curable paints have excellent productivity compared to other paints, and due to the Green Advantage that emits very little VOCs into the atmosphere Has been applied throughout.

In general, molded articles such as plastic bottles, telephones, sheets, and films are made of acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate (PC), polybutylene terephthalate (PBT), and polyethylene terephthalate (PET) due to processability. ), Polystyrene (PS), polyvinyl chloride (PVC) material and the like. The coating composition containing the photocurable oligomer was applied to such a material, which was to improve the hardness, durability, chemical resistance, and abrasion resistance of the molded article, but it was not a level that could fully satisfy the needs of consumers. . In addition, in the case of the plastic molded article as described above, the flexibility and hardness of the paint are required at the same time.

Examples of conventional photocurable coating compositions include Korean Patent Nos. 74985, 0103647, 0089390, US Pat. Nos. 3,782,961, 3,829,531, 3,874,905, 3,891,523, 3,895,171, and 3,899,611. And 3,912,516, 3,932,356 and 4,301,209, but the coating composition was not excellent in flexibility, hardness, chemical resistance, adhesion.

That is, when the conventional photo-curable UV paint is applied to flexible molded products such as plastic bottles, the flexibility is poor, resulting in cracking and poor adhesion of the paint. In addition, even if the flexibility is good, the scratch resistance and abrasion resistance was poor due to the poor hardness.

Accordingly, the present inventors are trying to solve the problem that the conventional photo-curable coating composition cannot satisfy the flexibility and hardness at the same time when applied to a material requiring flexibility such as plastic bottles, telephones, sheets, films, and the like, urethane acrylic As a result of using a late oligomer and adding a specially modified polyfunctional monomer, a reactive monomer, a photoinitiator, a photosensitizer, and the like, it was found that excellent flexibility, hardness, and ultraviolet curability were shown, thereby completing the present invention.

Accordingly, an object of the present invention is to use a coating composition using a photocurable urethane acrylate resin and a specially modified polyfunctional monomer, a reactive monomer, a photoinitiator, a photosensitizer, and the like that require flexibility such as plastic bottles, telephones, sheets, and films. To provide a coating composition excellent in flexibility and hardness, UV curing, wear resistance, weather resistance, chemical resistance when coating.

The photocurable coating composition of the present invention for achieving the above object is 10 to 70 parts by weight of a urethane acrylate represented by the following formula (1), 10 to 30 parts by weight of a special modified polyfunctional monomer, 10 to 50 parts by weight of a reactive monomer, It is characterized by including 0.1 to 20 parts by weight of the photoinitiator, 0.1 to 20 parts by weight of the photosensitizer, 10 parts by weight of the leveling agent and a small amount of the additive.

R ₁ is a hydrogen atom or a methyl group,

R ₂ is (CH ₂ ) _n or , (Wherein n is an integer of 2 to 6, R ₄ , R ₅ and R ₆ are the same as or different from each other, at least one is a linear alkyl group which is a methyl group, and R ₇ is an aliphatic, alicyclic or aromatic compound); ,

X is (Where b is an integer of 5 to 20, c is an integer of 2 to 5, and Y is a hydrogen atom or a methyl group).

The present invention will be described in more detail as follows.

(1) photocurable urethane acrylate oligomers

The photocurable urethane acrylate oligomer used in the present invention is represented by the formula (1), which is a dihydroxy functional polymethacrylate polyol represented by the following formula (2) of aliphatic, cyclic aliphatic diisocyanate or these isocyanate compounds It is prepared by reacting with some isocyanate functional group (NCO) in the oligomer, followed by addition reaction with the acrylate containing a hydroxyl group represented by the following formula (3).

Where

b is an integer of 5-20,

c is an integer of 2 to 5,

Y is a hydrogen atom or a methyl group.

R ₁ is a hydrogen atom or a methyl group,

d is an integer of 2-6.

In more detail, the polyol of the formula (2) used in the preparation of the photocurable urethane acrylate oligomer of the formula (1) is a dihydroxy functional polymethacrylate-based, in consideration of the curability and curable properties, such as hydroxyl value 30 ~ 1100, It is preferable to use the thing of molecular weight 100-4000.

The polyol and the diisocyanate compound are reacted to react primarily with the isocyanate monofunctional group.

Here, specific examples of the diisocyanate compound include isophorone diisocyanate, 4,4-dicyclohexyl methane diisocyanate, trimethyl-hexamethylene-diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4 -Trimethyl 1,6-hexamethylene diisocyanate, octadecylene diisocyanate, 1,4-cyclohexylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate and oligomers of these compounds Can be. In particular, the isocyanate oligomer may be a trifunctional triisocyanate of the biuret, isocyaurate structure of the diisocyanate, or a composite structure thereof.

The equivalent ratio of the diisocyanate compound and the dihydroxy functional polymethacrylate polyol during the first reaction is preferably used so that the dihydroxy functional polymethacrylate is 0.5 to 1.5 equivalents based on 2 equivalents of the diisocyanate compound. .

If the dihydroxy functional polymethacrylate polyol is less than 0.5 equivalents to 2 equivalents of the diisocyanate compound, the flexibility and impact resistance are poor, and if it exceeds 1.5 equivalents, the hardness, photocurability and chemical resistance are poor.

On the other hand, it is preferable to make a 1st reaction drip for 10 to 180 minutes, and to make it react, maintaining 10-180 minutes at 20-80 degreeC. If the reaction temperature is out of the above range may cause problems of resin properties and gelation.

After reacting the monofunctional group of the diisocyanate compound with the polyol as described above, the remaining one isocyanate functional group is reacted with the hydroxy group-containing acrylate represented by the formula (3).

Here, the hydroxy group-containing acrylate of the formula (3) is hydroxy ethyl acrylate, hydroxy ethyl methacrylate, hydroxy propyl acrylate, hydroxy propyl methacrylate, hydroxy butyl acrylate, hydroxy butyl methacryl Elate, hydroxy pentyl acrylate, hydroxy pentyl methacrylate, etc. are mentioned.

At this time, the equivalent ratio of the hydroxy group-containing acrylate of the formula (3) is preferably 0.5 to 1.5 equivalents relative to 2 equivalents of the diisocyanate compound. If the equivalent ratio of the hydroxy group-containing acrylate is less than 0.5 equivalents to 2 equivalents of the diisocyanate compound, the hardness, the photocurability and the chemical resistance are poor, and if the equivalent ratio is more than 1.5 equivalent, the flexibility and the impact resistance are poor.

In the secondary reaction, the reactant is added dropwise for 10 to 180 minutes, and then the reaction is maintained at 20 to 80 ° C for 10 to 180 minutes. If the reaction temperature is out of the above range, there may be a problem of deterioration of resin properties and gelation.

The manufacturing process of the above-mentioned photocurable urethane acrylate oligomer is shown in more detail as follows.

Isocyanate is weighed and attached to the synthesis apparatus in a four-necked round flask equipped with a thermometer, and then a dihydroxy functional polymethacrylate polyol and an appropriate amount of catalyst are weighed into a dropping tube and mounted in the flask. Then, the solution is added dropwise for 10 to 180 minutes while maintaining the temperature at 20 to 80 ° C, and the reaction is first performed. Then, after confirming the content of the specified isocyanate, the hydroxy group-containing acrylate is added to the dropping tube, if necessary, an appropriate amount of polymerization inhibitor is added to the dropping tube in a flask, and then maintained at 20 to 80 ° C for 10 to 180 minutes. The contents of the dropping tube are added at a constant rate and the reaction is carried out in the second reaction. When the reaction is terminated when the content of the final isocyanate reaches zero, a photocurable urethane acrylate oligomer according to the present invention can be obtained.

Thus obtained photocurable urethane acrylate oligomers obtained by dihydroxy functional polymethacrylate polyols and hydroxy group-containing acrylates exhibit excellent flexibility and hardness, chemical resistance, abrasion resistance and weather resistance.

The photocurable urethane acrylate oligomer as described above contains 10 to 70 parts by weight of the total coating composition. If the content is less than 10 parts by weight, the flexibility is insufficient, and if it is more than 70 parts by weight, the curability is insufficient.

(2) specially modified polyfunctional monomers

In the composition of the present invention, a specially modified polyfunctional monomer is used, which is added to improve curability. In general, although a polyfunctional monomer is used to improve the curability, when the general polyfunctional monomer is used, the curability is improved, but the flexibility is poor. In view of these conflicting physical properties, the following special polyfunctional monomers are used.

Specific examples include 1 selected from ethoxylated trimethylol propane triacrylate, ethoxylated trimethylol propane methacrylate, propoxylated trimethylol propane triacrylate, propoxylated trimethylol propane trimethacrylate, and the like. Species or two or more types of polyfunctional monomers may be mentioned.

Such a specially modified polyfunctional monomer is added in 10 to 30 parts by weight of the total coating composition, if the content is less than 10 parts by weight of the curability is insufficient, if more than 30 parts by weight there is a problem of poor flexibility.

(3) reactive monomer

Meanwhile, the composition of the present invention contains a reactive monomer, and specific examples thereof include 2-ethylhexyl acrylate, octyldecyl acrylate, stearyl acrylate, behenyl acrylate, trilydecyl methacrylate, and nonylphenol ethoxylate mono. Acrylate, beta-carboxyethyl acrylate, isobornyl acrylate, tetrahydrofurfuryl acrylate, tetrahydrofurfuryl methacrylate, 4-butylcyclohexyl acrylate, dicyclopentenyl acrylate, dicyclopentenyl oxy Monofunctional monomers such as ethyl acrylate, ethoxyethoxyethyl acrylate and ethoxylated monoacrylate; 1,6-hexanediol diacrylate, triphenylglycol diacrylate, butanediol diacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentylglycol diacrylate Ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol diacrylate 1 type, or 2 or more types chosen from bifunctional monomers, such as methacrylate, polyethyleneglycol diacrylate, polyethyleneglycol dimethacrylate, dipropyleneglycol diacrylate, and ethoxylated neopentylglycol diacrylate have.

When such a reactive monomer is added to 10 to 50 parts by weight of the total coating composition, if the content is less than 10 parts by weight, the flexibility is insufficient, if more than 50 parts by weight there is a problem of poor curing and chemical resistance.

(4) photoinitiators

As photoinitiators, conventional polymerization initiators activated by ultraviolet rays are used, and in particular, benzophenone series, benzyl dimethyl ketal series, acetophenone series, adraquinone series, thioxanthone series, acyl phosphine oxide series, and amino alkylphenes A non-system, a hydroxy alkyl phenone system, dialkoxy acetophenone system, a benzyl ketal system, etc. are mentioned. Specifically, 2-hydroxy 1,2-diperphenyl ethanone, 2-ethoxy 1,2- large phenyl ethanone, 2-isopropyl 1,2-phenyl ethanone, 2-butoxy 1,2- Diphenyl ethanone, 2-isobutoxy 1,2-diphenyl ethanone, 2,2-dimethoxy 1,2-diphenylethanone, 2,2-dibutoxy 1-phenyl ethanone, 1-hydroxy cyclo Hexyl phenyl ketone, dimethoxy hydroxy acetophenone, 1- (4-isopropylphenyl) -2-hydroxy 2-methyl propane, 2-methyl 1-4- (methylthio) phenyl-2-morpholino prop Panon, 2-benzyl 2-dimethylamino 1- (4-morpholinophenyl) -butanone or 3,6-bis [2-methyl-2-morpholino (propanoyl)]-butylcarbazole, bis (2,4,6-trimethyl benzoyl) -phenylphosphine oxide etc. are mentioned.

The photoinitiator is contained in an amount of 0.1 to 20 parts by weight in the total coating composition. If the content is less than 0.1 part by weight, the curability is poor, and if it is more than 20 parts by weight, the chemical resistance is poor.

(5) photosensitizers

The use of a photosensitizer is essential for rapid curing of the coating composition of the present invention. The photosensitizer effectively increases the activity of the polymerization initiator activated by the ultraviolet rays, thereby promoting ultraviolet curing of the paint. Photosensitizers include methyldiethanolamine, triethanolamine, ethyl 4- (dimethylamino) benzoate, 2-normal-butoxyethyl 4- (dimethylamino) benzoate, isoacryl 4- (dimethylamino) benzoate, 2 -(Dimethylamino) ethylbenzoate, 1- (4-dimethylaminophenyl) -ethanone, in addition to unsaturated copolymerized tertiaryamine oligomers, copolymerized amine acrylate oligomers, light replacing amine compounds previously filed by the applicant One or two or more selected from sensitizers (Application No. 93-31330) may be used in an amount of 0.1 to 20 parts by weight in the total paint composition. If the photosensitizer is added in an amount less than 0.1 part by weight of the entire coating composition, the curability is poor, and when it is added in excess of 20 parts by weight, the chemical resistance is poor.

(6) Leveling agent

As a leveling agent, the compound of a silicone diacrylate type and a silicone polyacrylate type can be used within 0-10 weight part of all the paint compositions.

(7) other additives

In addition, when semi-gloss or matte is required for the coating composition, the matting agent may be added within 10 parts by weight of the total composition depending on the required gloss.

On the other hand, when painting the coating composition on the plastic molded article, the painting operation can be used, such as spraying, dipping or roller coating method, among which can be selected an advantageous method according to the material of the plastic, the shape of the molded article and the paint thickness.

Different viscosity is required depending on the coating method, which can be used by adjusting the viscosity by adding an appropriate amount of volatile solvent. Volatile solvents facilitate the painting and smooth the appearance. Examples of the solvents that can be used include ketones, acetates, aromatic compounds, and high-boiling aliphatic hydrocarbon compounds, and can be used alone or in combination of two or more thereof. The amount of solvent used can be used with varnish / solvent weight ratio of 4/1 to 1/4.

In addition, as other additives, antifoaming agents and the like can be used according to the properties of known compounds, of course.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments as follows, but the present invention is not limited to the examples.

Preparation Example 1 Preparation of Urethane Acrylate Oligomer

1.0 equivalent of a dihydroxy functional polymethacrylate polyol (Diol BD 1000, Gold Schmidt, Germany) was inserted into a four-necked round flask with a catalyst and a polymerization inhibitor, and the temperature was 40 DEG C after attaching a condenser, a stirrer, and a thermometer. The temperature was raised to. Thereafter, 2 equivalents of isophorone diisocyanate trimer (manufactured by Olin, product name: LUXATE ITM 800) were added to the dropping tube, and the mixture was added dropwise for 1 hour, and reacted for 1 hour while maintaining 45 ° C. Thereafter, 1.1 equivalents of hydroxyethyl acrylate was added to the dropping tube, followed by dropwise addition for 30 minutes, and the reaction was carried out at 65 ° C. until the isocyanate content became 0 to prepare a urethane acrylate oligomer.

Preparation Example 2 Preparation of Urethane Acrylate Oligomer

2.0 equivalents of isophorone diisocyanate trimer (product of US Olin, product name: LUXATE ITM 800) were added to a four-necked round flask with catalyst and polymerization inhibitor, and the temperature was raised to 40 ° C. after condenser, stirrer and thermometer were installed. I was. Thereafter, 1.0 equivalent of polyethylene glycol (manufactured by Korea Polyol, product name: KONIX PEG-1000) having a molecular weight of 1000 was added to the dropping tube, and the mixture was added dropwise for 1 hour, and reacted for 1 hour while maintaining 45 ° C. Thereafter, 1.1 equivalents of hydroxyethyl acrylate was added to the dropping tube, followed by dropwise addition for 30 minutes, and the reaction was carried out at 65 ° C. until the isocyanate content became 0 to prepare a urethane acrylate oligomer.

Example 1

444 parts of photocurable urethane acrylate oligomers prepared in Preparation Example 1, 200 parts of ethoxylated trimethylol propane triacrylate (Mwonwon Corporation name: TMPEOTA), 1,6 hexanediol diacrylate (MIWON Corporation) ) 106 parts, isobonyl acrylate (SK-UCB product name: IBOA) 100 parts, photoinitiator (Ciba-Geigy company product name: D1173, propyl ketone) 40 parts, photosensitizer (Kumgang Goryeo Chemical, acrylamine) 50 parts, leveling 10 parts of (SK-UCB Co., Ltd. EBECRYL350, silicone type) were stirred to prepare a photocurable coating composition having a viscosity of 300 cps at 25 ° C.

Example 2

444 parts of the photocurable urethane acrylate oligomer prepared in Preparation Example 1, 300 parts of propoxylated trimethylol propane triacrylate (trade name: TMPPOTA), 1,6 hexanediol diacrylate (trade name: HDDA) ) 106 parts, isobonyl acrylate (SK-UCB trade name: IBOA) 100 parts, photoinitiator (Ciba-Geigy trade name: D1173) 40 parts, photosensitizer (Kumgang Goryeo Chemical) 50 parts, leveling agent (SK-UCB company) EBECRYL350) was stirred at 10 parts to prepare a photocurable coating composition having a viscosity of 300 cps at 25 ° C.

Example 3

444 parts of the photocurable resin prepared in Preparation Example 1, 300 parts of propoxylated trimethylol propane triacrylate (trade name: TMPPOTA), 106 parts of polyethylene glycol diacrylate (trade name: PEG400DA), photoinitiator ( 40 parts of Ciba-Geigy brand name: D1173), 50 parts of photosensitizer (SK-UCB company name: P115) and 5 parts of leveling agent (SK-UCB company EBECRYL350) were stirred, and the photocurable coating composition having a viscosity of 330 cps at 25 ° C. Was prepared.

Comparative Example 1

444 parts of epoxy acrylate (SK-UCB company name: EBECRYL 3700), 200 parts of pentaerythritol triacrylate (SK-UCB company name: PETA), 200 parts of trimethylol propane triacrylate (trade name: TMPTA) 106 parts of 6-hexanediol diacrylate (trade name: HDDA), 40 parts of photoinitiator (Ciba-Geigy company name: D1173), 10 parts of leveling agent (SK-UCB company EBECRYL350), and the viscosity was 25 A photocurable coating composition was prepared.

Comparative Example 2

444 parts of the photocurable urethane acrylate oligomer prepared in Preparation Example 1, 200 parts of pentaerythritol triacrylate (SK-UCB company name: PETA), 200 parts of trimethylol propane triacrylate (trade name: TMPTA), 1 106 parts of 6-hexanediol diacrylate (trade name: HDDA), 40 parts of photoinitiator (Ciba-Geigy company name: D1173), 10 parts of leveling agent (SK-UCB company EBECRYL350), and the viscosity was 25 A photocurable coating composition was prepared.

Comparative Example 3

444 parts of photocurable resin prepared in Preparation Example 2, 100 parts of pentaerythritol triacrylate (SK-UCB company name: PETA), 200 parts of ethoxylated trimethylol propane triacrylate (trade name: TMPEOTA) 106 parts of 1,6 hexanediol diacrylate (Miwon Corporation brand name: HDDA), 100 parts of isobornyl acrylate (SK-UCB name: IBOA), 40 parts of photoinitiator (Ciba-Geigy company name: D1173), leveling agent (SK 10 parts of UCB EBECRYL350) was stirred to prepare a photocurable coating composition having a viscosity of 300 cps at 25 ° C.

Experimental Example

The photocurable coating compositions obtained according to Examples 1 to 3 and Comparative Examples 1 to 3 were applied to PET (polyethylene terephthalate) moldings and then subjected to comparative tests. In the test described below, methyl ethyl ketone (MEK) and toluene, which were mixed solvents, were diluted to 50% by weight in a photocurable coating composition to a weight ratio of 1/1 to a weight ratio, and a PET spray test piece was sprayed using a spray coating machine. After coating, the solvent was volatilized at 50 ° C. for 2 minutes, dried, and then cured with UV curing energy of 800 mJ / cm 2 (UV irradiation apparatus: manufactured by American American Ultra Violet Co., Ltd.) to compare physical properties. The results are shown in Table 1 below.

Here, physical property evaluation was performed according to the following method.

1) Flexibility: Drop test-After the drop at 50cm height with 1kg weight, the paint was visually inspected.

2) Adhesion: It was measured according to JIS D0202 (Cross-Cut, Tape Test).

3) Abrasion resistance: 1000 times was measured by CS-10, 1000g Load using a dual abrasion degree meter (Model 505 of Teledtne Taber).

4) Hardness: denoted as pencil hardness (Uni-Pencil (Mitsubishi)).

5) Weather resistance: After being left in sunlight for 7 days, discoloration (yellowing) was observed.

6) Alcohol resistance: After immersion at room temperature for 24 hours in 50% ethanol aqueous solution was observed the paint state.

7) Alkali resistance: After immersion for 24 hours at room temperature in 1% aqueous sodium hydroxide solution, the coating state was observed.

8) Saline resistance: After immersion at room temperature for 24 hours in 5% aqueous sodium chloride solution, the paint state was observed.

9) Photocurability: After UV curing at a curing energy of 800 mJ / cm 2 (UV irradiation device: manufactured by America Ultraviolet, USA), the coating state was visually observed.

Example Comparative example One 2 3 One 2 3 flexibility ○ ○ ○ × × × Adhesion 100/100 100/100 100/100 90/100 100/100 80/100 Abrasion Resistance (mg) 3 5 7 8 5 15 Hardness 2H 2H H 2H 2H H Weather resistance ○ ○ ○ ○ ○ ○ Chemical resistance Alcohol resistance ○ ○ ○ ○ ○ △ Alkali resistance ○ ○ ○ △ △ △ Saline resistance ○ ○ ○ ○ ○ △ Photocurable ○ ○ ○ △ ○ △ (Note) ○: Good, △: Somewhat poor, ×: Poor

From the results of Table 1, the photocurable coating composition comprising a specially modified polyfunctional monomer, a reactive monomer, a photoinitiator, a photosensitizer and a leveling agent in the urethane acrylate oligomer according to the present invention is more flexible than conventional photocurable coating compositions. And it can be seen that the hardness, wear resistance, weather resistance, chemical resistance and ultraviolet curing excellent.

As described in detail above, a specially modified polyfunctional to urethane acrylate oligomer obtained by reacting a dihydroxy functional ?? limetaacrylate polyol with an isocyanate compound and addition reaction with a hydroxyl group-containing acrylate according to the present invention. Paint composition made by adding monomer, reactive monomer, photoinitiator, photosensitizer, etc. has excellent flexibility and hardness, excellent UV curability, excellent wear resistance, weather resistance, chemical resistance, and other flexibility such as plastic bottles, telephones, sheets, films, etc. When applied to the required surface, it is possible to obtain a molded article excellent in workability and hardened material properties.

Claims (6)

10 to 70 parts by weight of the urethane acrylate represented by the following formula (1), 10 to 30 parts by weight of the specially modified polyfunctional monomer, 10 to 50 parts by weight of the reactive monomer, 0.1 to 20 parts by weight of the photoinitiator, 0.1 to 20 parts by weight of the photosensitizer, A photocurable coating composition comprising less than 10 parts by weight of a leveling agent and a small amount of an additive. Formula 1 R ₁ is a hydrogen atom or a methyl group, R ₂ is (CH ₂ ) _n or , (Wherein n is an integer of 2 to 6, R ₄ , R ₅ and R ₆ are the same as or different from each other, at least one is a linear alkyl group which is a methyl group, and R ₇ is an aliphatic, alicyclic or aromatic compound); , X is (Where b is an integer of 5 to 20, c is an integer of 2 to 5, and Y is a hydrogen atom or a methyl group). According to claim 1, wherein the urethane acrylate oligomer represented by the formula (1) is a dihydroxy functional polymethacrylate (Dihydroxy-Functional-Polymethacrylate) polyol represented by the following formula (2) a monofunctional group of diisocyanate compound (NCO ), And then the remaining isocyanate functional group is obtained by addition reaction with a hydroxy group-containing acrylate represented by the following formula (3). Formula 2 Wherein b is an integer of 5 to 20, c is an integer of 2 to 5, Y is a hydrogen atom or a methyl group. Formula 3 R ₁ is a hydrogen atom or a methyl group, d is an integer of 2-6. The method of claim 1, wherein the special modified polyfunctional monomer is ethoxylated trimethylol propane triacrylate, ethoxylated trimethylol propane methacrylate, propoxylated trimethylol propane triacrylate, propoxylated trimethyl A photocurable coating composition, characterized in that one or two or more polyfunctional monomers selected from all propane trimethacrylate and the like. The method of claim 1, wherein the reactive monomer is 2-ethylhexyl acrylate, octyldecyl acrylate, stearyl acrylate, behenyl acrylate, trilydecyl methacrylate, nonylphenolethoxylate monoacrylate, beta-carboxyethyl Acrylate, isobonyl acrylate, tetrahydrofurfuryl acrylate, tetrahydroperfuryl methacrylate, 4-butylcyclohexyl acrylate, dicyclopentenyl acrylate, dicyclopentenyl oxy ethyl acrylate, ethoxye Monofunctional monomers selected from the group consisting of oxyethyl acrylate and ethoxylated monoacrylate; And 1,6-hexanediol diacrylate, triphenylglycol diacrylate, butanediol diacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentylglycol di Acrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol At least one difunctional monomer selected from the group consisting of dimethacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, dipropylene glycol diacrylate and ethoxylated neopentyl glycol diacrylate Photocurable coating composition. Metal vacuum deposition molded article which apply | coated the photocurable coating composition of Claim 1. The method of claim 5, wherein the metal vacuum deposition molded article is made of a material selected from the group consisting of acrylonitrile-butadiene-styrene copolymer, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polystyrene, polyvinyl chloride, and plastic bottle Metal vacuum deposition molded article, characterized in that selected from the group consisting of, telephone, sheet and film.